Bow for playing stringed instruments



April 3, 1956 K. M. VESTERGAARD 2,740,312

BOW FOR PLAYING STRINGED INSTRUMENTS Filed Sept. 7, 1954 INVENTOR United States Patent BOW FOR PLAYING STRINGED INSTRUMENTS Knud Michael Vestergaard, Viby, Jutland, Denmark Application September 7, 1954, Serial N 0. 454,423

9 Claims. (Cl. 84-282) The present invention relates to a bow for playing stringed instruments, such as violins, violas and violoncellos, and specially adapted for playing three or more strings at a time.

Such bows are known comprising in combination a string contacting band member consisting of a great number of parallel hairs, an oblong frame member in the form of a curved rod, means for connecting one end of the band member to one end of said frame member, an operating member swingably connected to said frame member at the other end thereof, and other connection means for attaching the other end of said string contacting band member to the operating member. While playing the player holds the thumb on said operating member and exerts a suitable pressure thereon so as to tighten more or less the string contacting band member. It is however, tiring for the player to exert a considerable pressure with the thumb, and some constructions have been proposed with the object to provide such means that the player can lock the operating member in a position in which the string contacting band member is tightened. Such means the player can utilize when the music to be played requires that the string contacting band member be tightened during a period of a considerable length.

The said known constructions are, however, so arranged that the player shall perform a separate release operation when he, after having played with the tightened string contacting band member in locked condition, he shall play with the said band member in a loosened condition. The said release operation of the known constructions necessitate a short interruption of the flow of the music. The correct performance of the music can, therefore, not be accomplished by means of bows with lock means of hitherto known constructions.

It is an object of the invention to provide a bow for the said purpose having locking means for the operating member to be operated in such a manner that the flow of music is not interrupted on account of a change in the tension of the band.

It is a further object of the invention to provide a bow in which the locking as well as the un-locking of the operating member can be accomplihed by swinging the operating member in a direction to tighten the band mem her and subsequently giving the operating member freedom to swing.

It is also an object of the invention to provide a bow, having means for adjusting the tension of the band member in the locked condition of the operating member.

It is also an object to provide a lock mechanism which will operate smoothly and with great security.

These and other objects will be evident from the following description taken in conjunction with the accompanying drawing, in which- Fig. 1 shows in side elevation a bow according to the invention, a so called Bach-bow,

Fig. 2 is a side view partly in section of the end portion of the bow, and on a larger scale than in Fig. 1,

ice

Fig. 3 is a side view partly in section of a portion of Fig. l, on a still larger scale,

Fig. 4 is a sectional view substantially on line IV-IV in Fig. 3, and

Figs. 5 and 6 are perspective views of cam means of the bow.

Referring to the drawing the numeral 1 designates a curved rod having a cross section substantially as a hexagon. To the one end of this rod is attached a metal tube serving as a connection means for the one end of a string contacting band member 3 consisting of hairs. A little piece of leather is disposed at the tube edge to prevent damaging the hairs on said edge.

At the other end of rod 1 is attached a wooden piece 4 provided with finger grips. This end of the rod has a bore for a threaded spindle 5 provided with a handle 6, Fig. 2, and guided in a recess 7 in the end face of rod 1. The spindle 5 is screwed through a nut member 8, Fig. 3, which is attached to a sliding member 9. Nut member 8 extends through a slit 10 formed in rod 1 and has its lower end screwed into the sliding member 9 which has a bore for a pivot pin 11 extending at a right angle to the bow plane. The shaft 11 serves for the swingable mounting of an operating member 12 provided with two rounded cut-aways 13 and 14 and a curved incision 15. Operating member 12 has a downwardly extending portion 16 in which is fastened a metal tube 17 serving as a connection means for the other end of the string contacting band member 3. In both tubes 2 and 17 the band member is locked by means of a wedge member 18 inserted from below. A piece of leather 19 is inserted in tube 17 to protect the band member from being damaged by the tube edge.

Along its rear side the operating member 12 has a recess 20 for a cover 21 which is provided with a turned-up margin portion 22 engaging a notch in operating member 12. Cover 21 is also provided with two bent-in corner portions 23 engaging cut-outs in operating member 12, and a depression 24 on either side engaging corresponding depressions 25 in operating member 12.

At the rear end of operating member 12 is attached a plate 26 extending in the plane of the bow. On one side of plate 26 is attached a cam member 27 for guiding a lock member or follower 28. Cam member is formed with a central protruding portion and around that a follower path comprising path divisions 29 and 31) at the sides, an upper path division provided by said plate 26 and a lower path division defined by an upper oblique edge 321, 322, 323 formed with a notch 33. Path divison 29 is arranged inclined so as to have increasing distance from plate 26 in the direction downwards. Path division 30 is arranged inclined so as to have increasing distance from plate 26 in the direction upwards. Below cam member 27 is disposed a plate member 34 on plate 26. Plate member 34 has its upper edge adjoining edge 321 and its thickness is smaller than that of cam member 27 at edge 321. Edge 321 thus provides a shoulder. Plate 34 is formed with a shoulder edge 35 near notch 33 substantially at a right angle to edge 321. Plate 34 has one edge adjoining the rear edge of operating member 12 and an other edge 36 formed as a shoulder edge substantially parallel thereto. The lower edge of plate 34 extends along the lower edge of plate 26.

In plate 26 is cut a slit extending along edge 36 to the sharp corner 324, Fig. 3 defined by edge portions 322 and 323. A portion 37 of plate 26 at the right hand side in relation to said slit is bent out of plane as shown in Fig. 4 to provide a step-down from the path portion at notch 33 to the portion 37.

Lock member or follower 28 is formed as a projection on an arm 38 having a portion 39 bent at a right angle to attests provide a swinging axis for said arm 33 and follower 28. Portion 39 is disposed in a bore 40 in sliding member 9. To permit removal of the arm 38 with follower 28 and portion 39 thesliding member 9 is'provided with two slits 41 and 42 at right angles in relation to each other so that arm 38, upon removal of cover 21 and releasing sliding member 9 from rod 1, can be swung to a position opposite the position shown in Figs, 3 and 4 so as to be in alignment with slit 42. From such position arm 38, can be withdrawn through said slit.

On sliding member 9 a suitably elastic rubber plug 43 is inserted in a recess and serves as a stop member for operating member 12. When follower 2.8 is in locked Position in notch 33 the said plug 43 will effect a pressure on operating member 12.

Sliding member 9 is guided by three side faces 45 of rod 1 and by edges 4.6 of two rails 47 disposed on ith sidesof rod 1 along handle portion 4.

In the position shown in Figs. 1 and 2 the string con.- tacting member 3 is tightened, ready for playing on one or two strings at a time.

In Fig. .3 lock member or follower 28 engages path 29 in such position that the band member 3 is tightened suitably for playing one or two strings at a time. The tension of the band member 3 is obtained by exerting a pressure on operating member 12, and the tension will be greater or less according to the pressure. The ineisionlS is shaped to engage the thumb in.

When the operating member .12 and the follower '28 are in the position shown :in Fig.3., and the thumb pressure on operating member ,is increased, the follower will pass down the path division 29 and pass by the shoulder edge 321. Ann .38 acts as a spring to press the follower inwards on the cam means, and the end of follower 28 will therefore contact :p'late member 34. When the thumb pressure then is lessened the :foliower 28 can not pass back past edge 321, but it will slide along this edge 321 beyond shoulder edge 3.5 .to notch 33. Follower 28 will here be ina locked position corresponding :to the tightenedcondition of the string contacting band member 3. 'When later on a considerable pressure is exerted on operating member 12 to tighten the band member .3 :the follower 28 will slide along shoulder edge 35 .and onto the plate portion 37. The follower 28 can, then, not pass directly back to notch 33, but when the thumb pressure on operating member is lessened the follower will, due to the step formation :44, move upwards at .the right hand side in relation to .corner 324 and into the :path division 30. Jmen the pressure is further lessened :the follower will pass up said :path division 30,-due to-the tension in band memher .3, and move past shoulder edge 31. The follower 28 can, then, not pass back directly to path division 30, but .it can move freely on plate '26 above .saidedge 3'1. When-a considerable :thuntb pressure is exerted on operating member 12 the shoulder ledge :31 will force .the follower 2810 the entrance to path division '29 and .into said path division 29. The operating member may :he swung to and fro so that the follower move to and .fro from the .plate 26 portion above tedgefii tota-pathdiyision 29 point above edge 321.

The bow can .thus the :used with the string contacting band member v3 in locked tightened position and with the followerZS.engagingnotch 3.3. This condition is utilized when during a period .'.of .a considerable length it is necessary .to:play.on "one .or two instrument strings at a time. The how .can :also the. :used with ifreely adjustable band member tension while the follower is in path division ,29 or on plate 26 portion above edge This condition is utilized when three or more instrument strings at afime are :to be played. The bow is converted from the first mentioned condition :to ;the last mentioned condition "by exerting a considerable thumb ".PI'ESSHZ'E on operating member 12 and subsequently releasing the operating member?12. The follower '28 will thereby pass :from notch 33 below comer 324 through 1path division 30 to plate 26 portion above edge 31, and the bow will then be in the second mentioned condition. in this condition the player can vary the band member 3 tension by varying the thumb pressure on operating member 12. The bow is converted from the condition of free adjustability to the condition with the band member 3 locked in tightened condition by exerting a considerable thumb pressure on operating member 12 so as to cause follower 23 to pass by shoulder edge 321 and subsequently releasing the thumb pressure. The follower will then move to notch 33. In this condition the playing can be performed without exerting a thumb pressure on the operating member 12. The follower can move around in the path only in one direction, and it will be noted that converting the bow condition is effected by a manipulation just as the manipulation required during playing with freely adjustable band memher 3, the only manipulations required being varying humb p ess r n op t ng u berush ma ipul n ca b performe duri g P ay ithou nter upting the music flow. I n

A face 48 on operating member 12 serves as a stop face coacting with a stop face 49 on sliding member 9 to pro e a op P s n r sp nd to a keued wadit o o b nd mber 3 nd l o r 28 in ppe most po ition on Pl e .26 po above ed e L i w ll b unde s ood ha th above desc be manner of c n truc on i lus a d i h a ompan n d wns shall se e ex lu iv y as an e a le nd ha ations are possibl withi the were of the n hus, the cam pa h mea s be a tached to t e s... we member 9 and the ollo e and it arm may b .s u ehh mounte o theeperat ns member- Th new s uls be va ed in dif e en manners as wil be ob ious to tho e s dlledz n t e a te .I d clare that w at c aim s:

A bow for st in d n t ument sompr s n n ou binati n a str ng cont n b nd mem er ai 91 9318 f me mem er, c nnecti n ns a one en o sa d frame m mber f r a ach ng o e and o sa d rin -.9r tacting ba d member o sa en o a f me wit I. n ope a i g mem e s ns ly conne t d to said ame member at the other end thereof, other connection means for attaching the other end of said string contacting band member to said operating member, an arm arranged swingable on saidframe member on an axis substantially parallel to the swinging axis of the operating membet, at :the free end of said arm a projection substan: tially parallel :to the arm swinging aXis to provide a cam follower, cam means comprising a central project on and a follower path arranged around said central projection substantially in .a plane at a right angle to the arm axis, the said follower path :being subdivided in at least two divisions .by shoulders extending substantially in planes having generatrixes -.parallel to the said arm axis and obliquely in relation to the longitudinal direction of said arm, and spring means for pressing said projection follower into the path, the said shoulders being-so arranged, that the said follower can pass from one path diyisiqn into another path division only 'invone direction.

2. A bow for playing stringed intruments, comprising in combination a string contacting band member, ,an long frame member, nnec ion means a o e en of said frame member for attaching one end of said st ning contacting band tmemherto said end of said frame-,member,..-an operating member swingably connected to id frame member at the .other end thereof, other v cpnn tionmeans for attaching the ,otherend of said string contacting band member to said opera-ting member, an arm arranged swingable on .said frame member on an axis substantially parallelto the operating member swinging axis, at the free end of said :a projection sphstantially-.-para-llel .to the arm swinging axis to provide a cam follower, cam means extending substantially in a plane :at a right angle to the arm ,axis and comprising a central :portion :projectingjrdm said plane towards said in relation to one arm and a follower path around said central portion, the said path being subdivided by shoulders extending substantially in planes having one generatrix substantially parallel to the arm axis and being arranged as step-downs way around the central portion and step-ups in relation to the opposite way round the central portion, spring means for pressing said projection follower into said path, each of which shoulders is arranged to have a generatrix at an angle different from a right angle in relation to the follower arm when the follower contacts the shoulder, the said angle being so that the follower pressure on the shoulder will force the follower in the direction of the first mentioned way around the central portion, and the said cam means having at a point remote from the arm axis a notch directed towards said arm axis to provide a stop point for the follower, and beyond said notch a shoulder so arranged as to permit the follower to be moved in a direction away from said notch into the next path division and to prevent its rearward motion.

3. A bow as claimed in claim 2, in which at least one cam path division nearest the arm axis is widened from said central portion towards said arm axis.

4. A bow as claimed in claim 2, in which at least one cam path division remote from the arm axis is widened from said central portion away from the arm axis.

5. A bow as claimed in claim 2, in which yieldable stop means are arranged between the operating member and the frame member.

6. A bow for playing stringed instruments, comprising in combination a string contacting band member, an oblong frame member, connection means at one end of said frame member for attaching one end of said string contacting band to said end of the frame member, an operating member swingably connected to said frame member at the other end thereof, other connection means for attaching the other end of said contacting band member to said operating member, coacting cam means on said frame member and said operating member comprising a follower and a cam path member therefor having a central cam portion and a path surrounding said central portion, the said cam member having stop means so arranged as to permit of the follower passing round in one direction in said path and preventing the follower from passing round in the opposite direction, and other band member tightening stop means arranged to stop the follower against such movement which is caused by tension in the string contacting band member acting on the operating member to swing it in relation to the frame member, and conduction means guiding the follower along the cam path, and stop means preventing the follower from returning directly to the band member tightening stop means.

7. A bow as claimed in claim 6, in which the frame member comprises a rod consisting of a number of sections having sides lying substantially in planes radially to the rod axis, the said sections being glued together along said sides.

8. A bow as claimed in claim 6, in which the frame member comprises a rod having polygonal cross section.

9. A bow as claimed in claim 6, in which the frame member comprises a rod of polygonal cross section having pivotal members for a part of the operating member arranged to be adjusted longitudinally along said rod guided by the sides of said rod.

References Cited in the file of this patent UNITED STATES PATENTS 1,714,490 Berkowski May 28, 1929 FOREIGN PATENTS 378,582 Germany July 20, 1923 

